It's just another summer day of hunting frogs for twelve-year-old Billy, Abby, and Toby, when they stumble upon a deserted lake cabin and meet Mary, a real live ghost, searching for her lost locket. The trio offer to help her find it and the Fantastic Phantasmic Detective Agency is launched. 

But when the youthful sleuths enlist the help of the grumpy medium, Mr. Monsento, to help them with their second case, locating a ghost's missing ghost brother, a mysterious visitor from the UnderWorld appears. Soon the agency is entangled in a conflict between rebellious spirits, undead Realm Walkers, officious OtherWorld Bureaucrats and traitorous UnderWorld Demon Ambassadors.

If you like your ghost stories with a twist and a dash of humor, you'll definitely enjoy this book.